|Mac & Cheese – Bob Krause|
I believe that the ruler's never been explained because it hasn't been well thought-out. Is it useful? Certainly. But it's also very "information noisy". The amount of information the ruler shows about the current selection is often more than users expect, want or can make sense of. This is particularly true of young and inexperienced users.
I contend that the ruler has been overburdened and that its function should be separated into two different tools and that the options available when positioning the ruler be expanded.
The ruler should display the distance between it’s origin and the current selection, but NOT also show the dimensions of the selection. I further believe that the user should be able to rotate the orientation of the ruler without having to dismiss the ruler, rotate the canvas and then re-place the ruler. Additionally, while the ruler is being placed Tinkercad should recognize the use of modifier keys to indicate either that the position of the ruler should ignore the current snap grid setting, perhaps using the shift key, or that the position of the ruler should magnetically snap to the edge of a shape within a certain distance, perhaps using the alt key.
A different tool, call it the "dimension tool", should be used to show the dimensions of the selection. Though, because the location of a dimension tool wouldn’t affect the display of that information, perhaps this dimensioning feature should be a mode of the canvas. If presented as a mode, under no circumstances should it be necessary for the user to open the "Edit Grid” dialogue to change modes, both because the dimensioning mode shouldn't necessarily be persistent and because the dialogue is too inaccessible from the mainline workflow.
Fix the ruler. Distance and dimensioning are orthogonal and not sufficiently inter-related to be conjoined as they are.